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Test Info:

<meta charset=utf-8>
<title>Largest Contentful Paint: src change triggers new entry.</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="resources/largest-contentful-paint-helpers.js"></script>
<img src='/images/lcp-1x1.png' id='image_id' width="133" height="106"/>
async_test(function (t) {
assert_implements(window.LargestContentfulPaint, "LargestContentfulPaint is not implemented");
let beforeLoad =;
document.getElementById('image_id').src = '/images/lcp-133x106.png';
const url = window.location.origin + '/images/lcp-133x106.png';
const observer = new PerformanceObserver(
t.step_func(function(entryList) {
let entries = entryList.getEntries().filter(e => e.url === url);
if (entries.length === 0)
assert_equals(entries.length, 1);
const entry = entries[0];
const size = 133 * 106;
checkImage(entry, url, 'image_id', size, beforeLoad);
observer.observe({type: 'largest-contentful-paint', buffered: true});
}, 'Largest Contentful Paint: changing src causes a new entry to be dispatched.');